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CSS Base

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Any URL's added here will be added as <link>s in order, and before the CSS in the editor. You can use the CSS from another Pen by using it's URL and the proper URL extention.

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Babel includes JSX processing.

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Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

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If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.

Editor Settings

Code Indentation

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                <div class="disclosure">
  <button aria-expanded="false" data-disclosure-trigger>Show/hide content</button>
  <div hidden class="disclosure__content">
    <p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Neque, aliquid esse nisi ut atque velit!</p>
    <p>Lorem ipsum, dolor sit amet consectetur adipisicing elit. Omnis quisquam expedita cum, saepe veritatis nulla delectus obcaecati voluptatem nihil dolore hic in, atque eligendi doloremque ab iste repellat, tempora eum.</p>
    <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Eveniet, eaque! Ullam, natus sapiente ea saepe quod quos, accusantium in hic et voluptate molestias doloribus omnis nostrum harum amet fugit. Neque.</p>


                :root {
  font-size: 110%;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial,
    sans-serif, "Apple Color Emoji", "Segoe UI Emoji";

button {
  font-size: inherit;
  padding: 0.5em;



                const triggerButton = document.querySelector("[data-disclosure-trigger]");
triggerButton.addEventListener("click", function () {
  let expanded = this.getAttribute("aria-expanded") === "true" || false;
  this.setAttribute("aria-expanded", !expanded);
  let content = this.nextElementSibling;
  content.hidden = !content.hidden;